719 



tude of la Boca de Manamo, Punta Baxa, and 

 Vieja Guayana. The Memoirs of Mr. Espinosa 

 have made known to us the real situation of 

 Punta Barima ; so that on correcting the abso- 

 lute longitudes by those of Puerto Espana in the 

 island of Trinidad^ and of the castle of Saint 

 Antonio at Cumana, (two points settled by my 

 own observations and the judicious researches of 

 Mr. Oltmanns,) I think I can furnish state- 

 ments sufficiently accurate. It is to be wished, 

 that the difference of meridian between Puerto 

 Espana and the little mouths of the Oroonoko, 

 between San Rafael (the summit of the delta) 

 and Santo Thome del Angostura, may some day 

 be determined by the chronometer in an unin- 

 terrupted voyage. The situation of the latter 

 as I have given it rests on that of Cumana, and 

 (by the confluence of the Apure) on Caraccas 

 and Porto Cabello*. 



* See ray Obs. Astr., vol, i, p. xxxviii. Espinosa, Memorias de 

 las Navegantes Espannoles, vol. i, p. 81, and the Carta esf erica 

 de Cvstas de Tierra Firrna de Don Joaquin Francisco Fidalgo 

 publicada en 1816, compared with the sketches of the Bocas 

 del Orinoco, which I procured at Angostura. The following- 

 are the results of my researches : Punta Barima, the eastern 

 bank of the great mouth ( Boca de Navios) of the Oroonoko, 

 corrected by Puerto Espana and Portorico, according to 

 Mr. Oltmanns, sixty-two degrees twenty-six minutes forty- 

 six seconds ; by Cumana, according to my direct observations, 

 sixty-two degrees twenty minutes ten seconds, 1 have thought 

 it right to fix on sixty-two degrees, twenty-three minutes, be- 

 because the Spanish navigators set out from the island of Trim- 



